Databases come in a variety of sizes. Some systems, such as shared-nothing, massively parallel processing (MPP) systems, store massive amounts of information, for example on the order of terabytes or petabytes. For owners of these databases, it is often very important that these databases be operational at full capacity. Downtime or even slower response times may be unacceptable. As a result, it is important that operations which are performed on these systems, such as management operations (e.g., to migrate a database to new hardware or update software) or access operations (e.g., to write data to the database), are well understood and/or do not cause the system to crash or slow down at inconvenient times. It would be desirable if systems were able to provide services and/or tools which made these operations easier to manage and/or easier to understand. For example, such services and/or tools may be used by developers (e.g., who are responsible for creating and/or maintaining operations performed on a database), or by users of the operations (e.g., database administrators who manage a database).